6.2 Measuring Electricity Flashcards
How does current form?
Current forms whenever charge flows from one object to another. Can be direct (DC) or alternating (AC).
What is direct current?
Direct current is supplied by a battery, its electrons flow along a wire in the same direction.
What is alternating current?
Alternating current is supplied by a power point, its electrons shuffle back and forth along the wire.
What is used to measure current?
An ammeter is used to measure current, it measures the amount of charge that flows through it every second.
What is the unit used to measure current?
Ampere, A, and amps.
What is used to measure voltage?
A voltmeter is used to measure voltage, it measures the amount of energy supplied to the charges and used by the charges.
What does it mean when the voltage is 0?
It means the battery is dead or the power point is turned off.
What is the unit used to measure voltage?
Volts and V.
Where do electrons get their energy?
Electrons get their energy from the circuits energy source.
What is a transformer used for?
A transformer is used to reduce the voltage, making it more manageable.
What is a battery?
a battery is a portable electrical energy consisting of wet cells, dry cells, and photovoltaic cells.
Advantages/disadvantages of a wet cell
- provide large voltages, lasts a long time, and can easily be recharged
- heavy and can leak
Advantages/disadvantages of a dry cell
- compact
- doesn’t leak
- can only power smaller things such as torches, toys, and remote controls
What is resistance?
A resistance is the restriction for electrons.
What does resistance meaure?
Resistance measures how difficult it is for an electric current to flow through a material.
